/*
 * This program is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program. If not, see <http://www.gnu.org/licenses/>.
 */
package net.sf.l2j.gameserver.model.zone.form;

import net.sf.l2j.gameserver.model.zone.L2ZoneForm;

/**
 * A primitive circular zone
 * 
 * @author durgus
 */
public class ZoneCylinder extends L2ZoneForm {
	private int _x, _y, _z1, _z2, _rad, _radS;

	public ZoneCylinder(int x, int y, int z1, int z2, int rad) {
		_x = x;
		_y = y;
		_z1 = z1;
		_z2 = z2;
		_rad = rad;
		_radS = rad * rad;
	}

	@Override
	public boolean isInsideZone(int x, int y, int z) {
		if (Math.pow(_x - x, 2) + Math.pow(_y - y, 2) > _radS || z < _z1
				|| z > _z2)
			return false;
		return true;
	}

	@Override
	public boolean intersectsRectangle(int ax1, int ax2, int ay1, int ay2) {
		// Circles point inside the rectangle?
		if (_x > ax1 && _x < ax2 && _y > ay1 && _y < ay2)
			return true;
		// Any point of the rectangle intersecting the Circle?
		if (Math.pow(ax1 - _x, 2) + Math.pow(ay1 - _y, 2) < _radS)
			return true;
		if (Math.pow(ax1 - _x, 2) + Math.pow(ay2 - _y, 2) < _radS)
			return true;
		if (Math.pow(ax2 - _x, 2) + Math.pow(ay1 - _y, 2) < _radS)
			return true;
		if (Math.pow(ax2 - _x, 2) + Math.pow(ay2 - _y, 2) < _radS)
			return true;
		// Collision on any side of the rectangle?
		if (_x > ax1 && _x < ax2) {
			if (Math.abs(_y - ay2) < _rad)
				return true;
			if (Math.abs(_y - ay1) < _rad)
				return true;
		}
		if (_y > ay1 && _y < ay2) {
			if (Math.abs(_x - ax2) < _rad)
				return true;
			if (Math.abs(_x - ax1) < _rad)
				return true;
		}
		return false;
	}

	@Override
	public double getDistanceToZone(int x, int y) {
		// Since we aren't given a z coordinate to test against
		// we just use the minimum z coordinate to prevent the
		// function from saying we aren't in the zone because
		// of a bad z coordinate.
		if (isInsideZone(x, y, _z1))
			return 0; // If you are inside the zone distance to zone is 0.
		return Math.sqrt((Math.pow(_x - x, 2) + Math.pow(_y - y, 2))) - _rad;
	}

	/*
	 * getLowZ() / getHighZ() - These two functions were added to cope with the
	 * demand of the new fishing algorithms, wich are now able to correctly
	 * place the hook in the water, thanks to getHighZ(). getLowZ() was added,
	 * considering potential future modifications.
	 */
	@Override
	public int getLowZ() {
		return _z1;
	}

	@Override
	public int getHighZ() {
		return _z2;
	}
}
